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DOI	10.1016/j.tecto.2021.228979
	The role of tectonic inheritance in the development of a fold-thrust belt and superimposed rift: An example from the São Francisco basin, eastern Brazil
	Rodrigues R.T.; Alkmim F.F.D.; Reis H.L.S.; Piatti B.G.
发表日期	2021
ISSN	00401951
卷号	815
英文摘要	The São Francisco intracratonic basin, eastern Brazil, hosts multiple sedimentary successions younger than 1.8Ga that witnessed major plate reorganizations since its generation. During the Brasiliano/Pan-African Gondwana amalgamation, in the Ediacaran-Cambrian boundary, the western half of the basin was involved in the Brasília foreland fold-thrust belt, which propagated eastwards deforming its Proterozoic-Paleozoic strata. Lately, as the South Atlantic rift evolved giving rise to the Brazilian continental margin, the basin was affected by extensional tectonism leading to the development of the Cretaceous Abaeté half-graben. During this episode, elements related to a prominent structure of the Brasília foreland fold-thrust belt, the João Pinheiro fault, were reactivated controlling the graben architecture. Aiming to unravel the evolutionary history of the fault zone since its nucleation until its Cretaceous extensional reactivation, we conducted a structural investigation based on field, well-tied 2D seismic data, and paleostress analysis. Our study revealed that the fault represents an emergent ramp of the basal detachment of the Brasilia foreland fold-thrust belt. Formed under EW-oriented shortening, the structure exhibits a gentle recces-salient geometry in map view, which reflects variations in the detachment depth influenced by pre-orogenic rift structures. Trains of NS-trending chevron folds are abundant and their high symmetry and dominance are expressions of the control exerted by mechanical stratigraphy and low-friction basal detachment. The superposed Abaeté half-graben developed under an extensional regime with a NE-trending maximum extension. Under this condition, a stratigraphic interface along the João Pinheiro fault zone was reactivated giving rise to the graben border fault. NS- to NW-oriented preexisting bedding planes were activated as small normal faults. Although newly-formed faults are present, reactivation is the most effective mechanism of extension accommodation. Therefore, this study provides insights on the influence of tectonic inheritance on the architecture, deformation pattern, strain/stress partitioning and evolution of both extensional and compressional intracontinental systems. © 2021 Elsevier B.V.
关键词	Intracontinental deformation Mechanical stratigraphy Reactivation Tectonic inheritance
英文关键词	Deformation; Metals; Seismology; Stratigraphy; Brazilian continental margin; Effective mechanisms; Evolutionary history; Mechanical stratigraphy; Paleostress analysis; Prominent structures; Stratigraphic interfaces; Structural investigation; Faulting; continental margin; deformation; extensional tectonics; fold and thrust belt; Gondwana; intracratonic basin; normal fault; rift zone; stratigraphy; Brazil; Sao Francisco Basin
语种	英语
来源期刊	Tectonophysics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/208060
作者单位	Departamento de Geologia, Escola de Minas, Universidade Federal de Ouro Preto, Ouro Preto, MG 35.400-000, Brazil
推荐引用方式 GB/T 7714	Rodrigues R.T.,Alkmim F.F.D.,Reis H.L.S.,et al. The role of tectonic inheritance in the development of a fold-thrust belt and superimposed rift: An example from the São Francisco basin, eastern Brazil[J],2021,815.
APA	Rodrigues R.T.,Alkmim F.F.D.,Reis H.L.S.,&Piatti B.G..(2021).The role of tectonic inheritance in the development of a fold-thrust belt and superimposed rift: An example from the São Francisco basin, eastern Brazil.Tectonophysics,815.
MLA	Rodrigues R.T.,et al."The role of tectonic inheritance in the development of a fold-thrust belt and superimposed rift: An example from the São Francisco basin, eastern Brazil".Tectonophysics 815(2021).